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Mouth ulcers
Mouth ulcers are common and should clear up on their own within a week or 2. But see a GP or dentist if you have a mouth ulcer that lasts longer than 3 weeks.
How you can treat mouth ulcers yourself
Mouth ulcers are rarely a sign of anything serious, but may be uncomfortable to live with.
They need time to heal and there's no quick fix.
Avoiding things that irritate your mouth ulcer should help:
speed up the healing process
reduce pain
reduce the chance of it returning
Do
use a soft-bristled toothbrush
drink cool drinks through a straw
eat softer foods
get regular dental check-ups
eat a healthy, balanced diet
Don’t
do not eat very spicy, salty or acidic food
do not eat rough, crunchy food, such as toast or crisps
do not drink very hot or acidic drinks, such as fruit juice
do not use chewing gum
do not use toothpaste containing sodium lauryl sulphate
A pharmacist can help with mouth ulcers
A pharmacist can recommend a treatment to speed up healing, prevent infection or reduce pain, such as:
antimicrobial mouthwash
a painkilling tablet, mouthwash, gel or spray
corticosteroid lozenges
a salt (saline) mouthwash
You can buy these without a prescription, but they may not always work.
How to rinse with salt mouthwash
Find a pharmacy
Non-urgent advice:
See a dentist or GP if your mouth ulcer:
lasts longer than 3 weeks
keeps coming back
grows bigger than usual or is near the back of your throat
bleeds or becomes more painful and red – this may be a sign of an infection
Although most mouth ulcers are harmless, a long-lasting mouth ulcer is sometimes a sign of mouth cancer. It's best to get it checked.
Information:
Coronavirus (COVID-19) update: how to contact a GP
It's still important to get help from a GP if you need it. To contact your GP surgery:
visit their website
use the NHS App
call them
Find out about using the NHS during COVID-19
Treatment from a dentist or GP
A GP or dentist may prescribe stronger medicine to treat severe, persistent or infected mouth ulcers.
Possible treatments include:
steroid mouth spray or steroid tablets that dissolve in your mouth
painkilling gels, ointments, sprays or tablets
mouthwashes to kill or remove any germs in your mouth
Check if you have a mouth ulcer
Mouth ulcers usually appear inside the mouth, on the cheeks or lips.
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Ulcers can also appear on the tongue.
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You may have more than 1 ulcer at a time, and they can change in size.
Mouth ulcers are not contagious and should not be confused with cold sores.
Cold sores appear on the lips or around the mouth and often begin with a tingling, itching or burning sensation.
Causes of mouth ulcers
Most single mouth ulcers are caused by things you can try to avoid, such as:
biting the inside of your cheek
badly fitting dentures, braces, rough fillings or a sharp tooth
cuts or burns while eating or drinking – for example, hard food or hot drinks
a food intolerance or allergy
damaging your gums with a toothbrush or irritating toothpaste
feeling tired, stressed or anxious
Sometimes they're triggered by things you cannot always control, such as:
hormonal changes – such as during pregnancy
your genes – some families get mouth ulcers more often
a vitamin B12 or iron deficiency
medicines – including some NSAIDs, beta blockers or nicorandil
stopping smoking – people may develop mouth ulcers when they first stop smoking
If you have several mouth ulcers, it can be a symptom of:
hand, foot and mouth disease, which also causes a rash on the hands and feet
oral lichen planus, which causes a white, lacy pattern inside the cheeks
Crohn's disease and coeliac disease (conditions that affect the digestive system)
a weakened immune system from having a condition like HIV or lupus
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Page last reviewed: 19 January 2021
Next review due: 19 January 2024
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